Nanosecond imaging of quantum dots in highly fluorescent media

摘要

Quantum dots are now recognised as valuable luminescent labels. Amongst their desirable characteristics is a relatively long luminescence decay time that can allow selective detection in the presence of shorter lived background fluorescence. Here we demonstrate that nanosecond time-resolved imaging of quantum dot samples is easily accomplished with a directly-gated cooled CCD system that does not require an image intensifier stage to achieve nanosecond time resolution. The approach is likely to find application both to imaging of quantum dots in the presence of autofluorescence from tissues and also for time-resolved measurements of resonance energy transfer from quantum dot donors to conventional acceptor labels.